Valve and pump for metering out material for capsulating machines and the like



y 1.9 R. E. MOULE 2,

VALVE AND PUMP FOR METERING OUT MATERIAL FOR CAPSULATING MACHINES AND THE LIKE Filed De'c. 11, 1948 4 Sheets-Sheet 1' ld 125 me 4 p m M B3 I //v V15 NTOE 2.5x 1 Maw/.5

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May 12, 1953 Filed Dec; 11,, 1948 R. E. MOULE VALVE AND PUMP FOR METERING OUT MATERIAL FOR CAPSULATING MACHINES AND THE LIKE 4 Sheets-Sheet '2 zxaspsz May 12, 1953' R. E..M'OULE VALVE AND PUMP FORE METERING OUT MATERIAL FOR CAPSULATING MACHINES AND THE LIKE Filed Dec. 11, 1948 4 Sheets Sheet 5 MU OHWMM- 6 9g W H W H U //vvENTo'/? E EX MOULE' ATTo E) May 12, 1953 5;, MOULE 2,638,052

VALVE AND PUMP FOR-METERING OUT MATERIAL FOR CAPSULATING MACHINES AND THE LIKE Filed Dec. 11, 1948 I 4 Sheets-Sheet 4 //VV/VTOR 46 REX E MOULE eral positions.

Patented May 12, 1953 2,638,052 VALVE AND PUMP FOR METERING our MA- TERIAL AND THE LIKE FOB- CAPSULATIN G MACHINES Rex Moule, Holden, Mass., assignor to Norton Company, Worcester, Mass., a corporation of Massachusetts Application December 11, 1948, Serial No. 64,788

The invention relates to apparatus for metering out liquids which can be thin free-flowing liquids on the one hand or thick viscous liquids on the other hand and the invention also relates to apparatus for metering out solids in a liquid vehicle, and with regard to its more specific features, the invention relates to apparatus for metering out material to fill capsules in a capsulating machine. In one aspect the invention may be embodied in a valve and pump mechanism to deliver simultaneously a plurality of measured quantities of material at spaced positions, and in I a specific form these several quantities are equal.

, One object of the invention is to provide an improved metering out valve and pump mechanism for a capsulating machine. is to provide valve and pump mechanism of the type indicated which does not leak. Another object is to provide a non-leaking mechanism of the class indicated which will not soon wear out. An-, other object is to provide a mechanism of the class indicated which operates freely, requiring little power and setting up littl or no strain on i the machine. Another object is to provide a valve V and pump mechanism which will not readily clog Another object and which can be easily cleaned.

Another object of the invention is to provide a precision sliding valve, especially one having a plurality of valve parts, which is very tight when inposition to pass the material, but which at other times is free enough to be readily shifted without the use of a great deal of power, thus combining delivery of material without clogging or leaking with a minimum of wear on the sliding element. Another object is to provide a mechanism having one or more of the features indicated which is adjustable to deliver a variable predetermined quantity of material at. the sev- Another object is to provide an apparatus of the type indicated which is rugged and dependable in operation and well adapted for successful use in a capsulating machine which 3 turns out a plurality of capsules for each cycle of operation of the machine. Another object is ,to provide a mechanism of the class indicated which can have a sliding or moving valve part accurate to only plus or minus many thousandths of an inch in thickness rather than to plus or minus two tenths of a thousandths of an inch, and which nevertheless will be more dependable I.. ,than a mechanism with the more accurate sliding member due to the mechanical features ,which-are a part of this invention. Another object is to eliminate precision in sliding fit of a valve o fthe classindicated without loss of ac-.

10 Claims. (Cl. 103-2) provide a sliding or shifting valve member with mechanism which automatically takes up for wear.

Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings illustrating one of many possible embodiments of the mechanical features of this invention,

Figure l is a plan view of a valve and pump mechanism constructed according to the invention,

Figure 2 is a front elevation of the mechanism,

Figure 3 is a. side elevation of the mechanism, certain parts being shown in section,

Figure 4 is a fragmentary view on an enlarged scale showing the cam and limit switch for operating the solenoid,

Figure 5 is a vertical sectional view taken on the line 5--5 of Figure 2 and as to a certain part on the line 5-5 of Figure 7,

Figure 6 is a fragmentary sectional view similar to Figure 5 but showing certain parts in a different position and as to one of them being a section along the line 6-6 of Figure 7,

Figure 7 is an elevation on an enlarged scale of a sliding valve member,

Figure 8 is an elevation on an enlarged scale of a pump block,

Figure 9 is an elevation of the rear of the machine showing the driving mechanism for driving the valve and pump mechanism.

The valve and pump of this invention are particularly intended for a capsulating machine of the type disclosed in my copending application Serial No. 48,912, filed September 11, 1948, Patent No. 2,549,327 of April 17, 1951; which is a continuation of my application Serial No. 538,761, filed June 5, 1944, now abandoned. The machine of my copending application makes capsules by forming a pair of ribbons of gelatine, bringing the ribbons together and forming pockets between them, filling the pockets with. material such as vitamins in a liquid vehicle, then by pistons 2'! since the material w ill 'usually be cylindrical they could; so far as the mechanical, functioning ofthe pump, is con f which ha as hown, n u es a as steel which, so far as this invention is concorned, constitutes a frame or support for the, mechanism. Secured to the wall in any suitable manner is a steel plate at. Referring now to Figures 3 and 5, secured to the plate 2!: is a 7 pump block 25 and in this block are formed a plurality of parallelbores 26 in which operate v, a plurality o Par l p s ns, 21 nd it by i 1 the i' 1. V I 253 that materias pumped. The bores '26 cementof the pis'tons 't 'i in the bores are thus pump chambers audit is desirable that he hrh wiha ge n iame an the as s, consists o o is h. a hahifireh l a by m nd n h c ar nce. c g o t h b es, s, a ided. F th .0 re s ns of h fsh hr he ha e 6 qeljhsdi hav man other. shap s. For im l easohst e ston i: are rr i hhz cy nd i and as illustrated tl iey are uni-diameter rods and n rder h t hey shall o on ami ths iamm hr are ieiably m de .5 i

' less steel and so is the pump block 35.

Th new, .1 exten hro h. c w, thr

" stu ffingbox members 28 and packing such as eather sedan-s wi hdth hsh c os hhs 30 inthe lolgclg Zfi intotlie. bores26, The pistons :11 ext nd t tporallel. 9 7.65. :3 hg is Yahweh lia 'allel bushings extending through it. The ush n s 1 9ll. 1 ar llel o s hich tend from braclzets 3i secured to thev steel plate 2|, to the pump bloc}; 2 5 extending into bores herein heperali l. iodsfi h ei' hehrac L hhdj he nhihh i hk, firh d' fixedl in no homes her s hh e r 34 Slides. nland dow eohg hus s im -ma in r fer b y nterm ien ln hs h s o ian. 115 9 1 5. Al of the pistons 27 are rigidly secured to thepistonblock h ah h hs' flj' r n nt fina H in the piston block '34'and through the'pistons- 2'! themselves.

Referring now to Figure 9, the machine has a motor upon the shaft lfi of which is a sprocket gear 4-'l-driv ing by means of a chain 48 af'sprocket gear 49 on a shaft-50- ofga speed. 1'67 ducing mechanism 5i. The output shaft '52; of the, speed reducing mechanism M has thereon a'sprocket gear 53 which drives, by means of a chain. 54 a sprocket gear 55 ona shaft 56upon which isanother sprocketgear 51 driving means of-a chain 58; a sprocketgear Et upon a shaft wand alsodriving a sprocket gear 6!; on a. shaft 62 and an idler 63 on a shaftii is used to take slack out ofthe chain 58;

The motor iii-and the-speed reducing mecl'ianism 55 are at- I ""tached toahorizontal shelf- 65 projecting from th'elwall 2B. The vario'us shafts fid; tog-s25 and 64 project to the rear of the wall}? While the shaft 82 extends through it; The shafts 56 and 60. have functions in the capsulating machine to be pumped in which are irrelevant to this pump and valve mechanism, but the shaft 62 is shown in Figure 5 and is journalled in a bushing 68 in the wall 20 and the steel plate 2! and has in front of the plate 2! in an integral crank pin '10 extending through a bore in a link 12 which reciprocates the piston block 34. p

The crank pin Ml rotates continuously but I desire to reciprocate the pistons intermittently,

that; is to say to cause the pistons 2'5 to dwell at the end of each stroke for a material length of time. Furthermore it is desirable that the st oke of the pistons should be adjustable. Re-

ferring now to Figures 2 and 5, extending through the ling; l2 and through an arm #5 is a pin 76. The arm is is slotted to receive the link 12 and: islikewise slotted at the left hand end, Figure 2, to receive the lower end of a block 11 to which it is pivotally connected by means of a pin 18. The block 77 issecured to the piston block 34-. As the crank pin t rotates, the/link if! acting through the pin Hi-oscillates the arm 'ill' on the pin it. Upward movement of the" arm 15 from the position shown in Figure 2 does not at first have any effect upon the piston block M but ultimately portions such as pads iii) on the arm "i5 engage the-bottom of the piston bloclc'34 and further upward movement of the arm 15 raises the piston block 3d.

The slot at the left hand end of the arm i5 is large enough to accommodate; the left hand I bushingtfi and near the right handend: of the arm 25 is another slot to accommodate the'right handbushing 35. Secured to the right hand end of the arm 1-5 is an invertedL-shaped-member 8% which, during downward movement of the arm it, eventually contacts an adjustable screw 82 located in a split boss which projects :forwardly from a downwardly inclined extension-84 of the pistonblock 34. Consequently, after a dwell, the downward movement of" the arm 15 causes downward movement of the piston block 34-- by-engagement ot the inverted L-shaped-'portion 8i with the screw e 2; The screw 82- can '7 be adjusted to varythe dwell at each' 'endof the stroke and when adjusted it canbe; rigidly securedin adjusted position by means of anscrew 35 extending through the split in the, split boss 93;; However, perhaps a more importantiunction achieved by this mechanism is-that the stroke-of all of the pistons 21! can-{by adjustmen-t of'the screw- 82, be varied in length from zero to the maximum stroke provided by the eccentricity of the-crank pin 7%; The fragmentary section of Figurerfi showsa piston ZT-at the top or its stroke and in this illustrative embodiment of the invention the topposition of the pistonsis invariable; The section of- Figure 5 shows a. piston 27 nearly in its lower-most positionfor the adjustment indicated in Figure 2 but by adjusting the screw 82 this lowermost-position can be varied-from the top position shown in Figure 6 tea position where allof the pistons fl are level-withthe bottom of-the-boi'es fili. Thereby the amount ofmedican ient or other filling material beingv pumped into the capsules can be varied withinwide limitsl This accurateadjustability is highly desirable in a capsulating machine; In this connection I preferably provide scale marks 8? on the member 3i and a line 88- ona member 351- attached to the piston block 3 1 so that the operator may knowthe quantity of medicament-being delivered for each capsule.

Referring again to Figure 5; extending from each bore 26 to the front of thepump block 25 is a bore 99 constituting a passage. Above each bore 99 is another bore 9| extending from the front of the block 25 into a chamber 92 which is connected to all of the bores 9| which constitute passages for filling material to flow from the chamber 92. Secured by screws 93 to the top of the piston block 25 is a cap 94 of the shape indicated in Figures 1 and 5 and this cap is slotted to provide a continuation of the chamber 92, the shape of which will be apparent from a comparison of Figure 5 with Figure 1. The block 25 and cap 94 might be made out of one piece of steel but; it is simpler to manufacture them out of two pieces as indicated. Secured to the cap 94 by means of screws 95 is a top plate 96 having a slot 91 of the same area as the chamber 92 and in effect forming a continuationof it and this slot 91 opens to the inside of a tank 98 the bottom opening of which has the same shape as that of the slot 91 and the end and side walls of which are welded to the top plate 96 so that the chamber 92, the slot 91 and the tank 98 form a continuous enclosure opening into the several bores 9| (ten of them in this illus-' trative embodiment) for holding a quantity of medicament and delivering it to all of the bores 9|. A feature of the construction is that the walls of the chamber 92 are at a fairly broad dihedral angle to each other and the chamber 92 has a breadth extending beyond the marginal bores 9| so that the medicament does not have to rest in any narrow passage or passages until it comes to the bores 9| which are quite short and in which a given quantity of the medicament will not remain for more than one or a few strokes of the pistons 21. In handling material of this nature it is important that there should be no narrow passages where the material moves slowly and wherein the solid particles might gather together to form a lump and for the same reason it is important that there should be no spots in which medicament can remain without moving. By providing the broad chamber 92 with tapering walls, I have succeeded in avoiding any clogging or caking of the material.

Referring now to Figures 5, 6 and 7, I provide a movable valve member I 99 which has ports I9| and ports I92. shown connecting the bores 9| and 99 and a piston 21 is shown in its top position about to move down and when it moves down it will draw material from the chamber 92 through the bore 9| and through the port |9I into the bore 99 to bring the ports I92 in position to connect the bores 99 with passages I93 in the piston block 25. In Figure 5 the single piston 21 is shown nearly at its lowermost position for that particular adjustment and aboutto move upwardly and when it does move upwardly itdrives material out of its bore 26 and drives material ahead of it out of the bore 99 and through the port I92 into the passage I93 and into a pipe I94 in a...

header block I95. At the same timeall the other" In Figure 6 a port |9| is pistons 2! act likewise; there being. in this illustrative embodiment ten pistons 21,-ten. bores 29, ten bores 99, ten ports I92, ten passages I93 and ten pipes I94, and at a single upward stroke of the piston block 34 medicament is pumped into every one of the ten pipes I94 and the same amount is pumped into each. There is a single header block I95 which holds all of the pipes I94 in line with the passages I93 and this is secured as by screws I96 to the lower front corner of the piston block 25 which is cut off at an angle as shown. Comparing Figures 2 and 5,

it will be seen that the collection of pipes I94 plane perpendicular to the first mentioned plane.

All of these pipes I 94 extend into a header block I I9 which is clamped to a header block into which extend mandrel pipes 2 which deliver medicament between the ribbons of gelatin and around which mandrel pipes I I2 the gelatin ribbons are pressed to form tubular pockets to receive the medicament; thereafter by mechanism described in my copending application capsules are formed out of pockets but this need not further be described herein. As indicated in Figure 5 the headers H9 and I attach the mandrels II 2 to the pipes I94 so that each mandrel 2 receives all the medicament delivered by a particular pipe I94. As indicated in Figure 3, one of the header blocks for example the header block II I is attached to the wall 29 to support both of them and thereby the pipes I94 and the mandrels II2.

Referring now to Figure 9, upon the shaft 92 is a sprocket gear |I5 driving a chain ||6 which drives a sprocket gear I I1, an idler sprocket gear II8 being provided to keep the chain II 6 taut. The sprocket gear II! is keyed to a shaft I29. Referring now to Figure 1, the shaft I29 is journalled in a bushing |2I secured to the rear of the wall 29 and the shaft I29 extends through the wall 29 to the front side thereof. On the front of the shaft I29 is a cam I22 havin a hub I23. Inside of the hub I23 is a spring detent I24 which can be seated in either of two holes I25. Integral with the cam I22 is a knob I26 extending to the front of the machine in convenient reach of the operator. This knob I26 extends through a slot I27 in the movable valve member I99 which extends a goodly distance to the right of the pump block 25 and associated parts as clearly shown in Figure '1. Secured to the rear of the movable valve member I99 are blocks, I39 and I3I by means of screws I32 and I33. The block I39 extends farther to the rear than does the block I3I. When the operator pulls theknob I29 to locate the cam I22 in the position shown in Figure 1, it acts upon both of the blocks I39 and I3I and consequently re- -ciprocates the valve member I99, but intermittently with a dwell between each stroke because of the spacing of the blocks I39 and |3| relative to the cam I22 as shown in Figure 1. But when L the operator pushes the knob|26 to move the cam I22 rearwardly on the shaft I29, the cam I 22 can no longer act upon the block I3| but it can act upon the block I39 and therefore the movable valve member I99 stays to the left or is shifted to the left and thereafter stays to the left without further reciprocation until the knob I26 is again pulled forward. When the movable fvalve member I99 is to the left the ports I 9| 'con'nectthe bores "99with the bores 9| as pasms 7 shown in Figure 15 and then the pistons 2 aghtate the material leackan-d forth in these bores through the ports Hli without pumping it.

This agitation 'keeps'the medicament from congealing.

The :movable "valve member 1353 has one face against the pump :block 2:5 as -=clearly shown Figures 5 and-o. The cross section of this mem- -ber ideas shown in Figures 5 and 6 is :a rectangle and the three other races shown in these figures lit snug-1y the three faces of a rectangular slot '1 it which extends clear across a block Ml attachedbynuts :on threaded studs M3 to the pump block the studs M3 extending from threaded holes, not shown, the pump :block :25 through uncles, not shown, in the block Isl. The --foregoing constitutes a support .for slidably holdin the Velaemember HM adjacent the pump .blocl: 25.

A particular feature of invention is the provision of means to force the valve member l-ilil tightly against the pump block between strokes of the valve member illll, that is to say when it is not .moving, but releasing the valve member ,iilfi frompressure during the entire time ofeverystroke thereof. This feaiarre has several advantages in that, provided the front face rGf the pump block .25 is g round to a plane .fair-ly acouraltelyand thereariaceef the valve member Jill] is ground to .a plane fairly accurately, .an exceedingly tight and close fit is achieved between thepump block '25 and the valve member 196 so that when the valve .rnem'ber It!) is in "the pos'ition shown in Figure '5 the ports W2 are substantially continuations of the bores Jill) and the passages m3 and when the valve member I it is in "thepositions'hown in Figure 16 the ports i5! are substantially continuations of the bores "90 and ill and there willbencleakage of medicament and nevertheless the thickness of the valve member H "horizontally does not have to be kept to close tolerances and furthermore wear .onth'e valve member Hill is automatically "taken up and yet the valve member Jim} requires little ,force to mcve it. The mechanism for achieving these results will ."no-w be described.

"Still referring'to "Figures "5 and 6, a .long rod lfillfitstin'ai'ectangularslot lid! extending clear across the block t4"! and opening into the rectangular-slot 'l lil. "The rod its 'fitsnicely'inthe rectangular 'slot "f5?! and has a .flat i152 .exten'd- 'ing along its entire length. Referring now to Figures '1 and '2, at the left hand end of "therod 1-50 isan enlargement lei; "and attain right hand end man-enlargement l The-enlargement 953 extends through a split hole H35 in 'a lever "$56 which is securely clamped to the enlargement by means of a screw 15.? extending across the slotted part or the split hole T55. A spring I58 extends from a screw N59 to "the lever 156 into which it is hooked through a hole "I160 as clearlyshovv'ninifiigure 3. The screw'lEQ projects from the end of the plate M. This spring 1'58 exerts alight force on .the lever I56 to apply a couple "to the'lon'g 'rod lot which by reason ,of

the fiat I52 thereon lspressed against the valve member .lllil. This light clamping force does. not

.prevent easy .Tsliding of the valve member JTDD but stopsleakage as theports till and [0.2 move .into and out or .positionand prevents medica- 1 merit "from becoming lodged between the .plane faces oi the valve member 100 .and .the ,pump block'iii. Whemhowever, the valve ,memher @lllfl isat rest -a. stron iorce. -isiexerted .upon'the lever nothrustthevalve member wt against the pump .25 with great force. To that endl provide-a solenoid J65 having a .coil and a core it] to which is :pivotally attached by a pin .1518 a threaded rod its having an enlarged portion l lllhavi-ng a hole tor the pin E58. Thesolenoid E55 is secured to the wall it while the rod [8.9 extends through a hole H3 in a narrow lower end ,portion i-l 'l of the lever I55. A spring upon the rod its extends between .a washer H26 against the portion lid and nuts ill .on therod 8.6.9 so that when the solenoid 55 is energized it can .seat (thus avoiding vibration due to the .iact 'it will customarily be energized by .alte'rhat ing current) and when the solenoid seats the spring l'iii which is relativelystiff urges the lever [153 in a clockwise direction, Figure 13, to exertby .reas onof the leverage a verystrongiorce clamping the valve member it}! and the pump block "25 togetheras above mentioned. I'may also-prov'ide nuts 118 and a rubber washer E19 on the threaded rod 189 to tighten the spring H5.

Referring to Figures 1 and l, upon the shaft L429 is keyed a cam mil which has lobes till to engage a roller i822 on the arm it? of a limit switch its secured to the wall "26. Twice during every rotation of the shaft 9.28 the limit switch w lls closed and this limit switch i851 is connected in series with thesolenoidjl $5 and a source of power "to :actuate the solenoid W5 whenever the valve member Hill is at rest. Alternating current power is mentioned because this :is the power usually available in shops and factories of all kinds and the machine operates satisfactorily "with alternating current of any usual variety such as "th 60 cycle current "or the 25 cycle current which are usually available in the United States but will operate upon other frequencies. Direct current, if available, would be even better.

In order to secure "the purnp block 'Zi to the plate 2| without drilling any more holes from front to back of the pump block 25 may, as shown in Figures *1 and secure clocks F90 *to the pump block 25 by means of screws $91 and secure these leeks i'ilil to the plate by means of screws F92.

it has .heen men'tioned that the pistons HIE-"an the 1 pump block 25 are preferably made (of stain- ?lesszsteel. Alsonther parts viliichiare contacted my the medicament should %be :made :Joi ESlZEiIlIK-ISS steel :or other unaterlal which will not containihate the medicament pr :at least their surfaces which are-contacted lay the medicament should :haue amoating of non-wcontaminating metal or porcelain or the like. This includes the :tank 8 and the .movable valve .member I01] as \well .as-the pipes .i-llmand the mandrel pipes H2.

it will be .seen that the rod 15%] with its long (flat 1.52 .isin effect .an eccentric shaft andnalong its whole length acts .asa cam for pressing the .slide valve .lilll against the pump .block 25. It will .iurther be .seen that when the lever I56 has pressure put thereon by the spring I58 .01 .the solenoid a couple exerted .on the rod 1.50 .exertingpressure against the slide valve .108 all along its length. Other cam or eccentric devices could 'be .used .and, so far .as the 'brcad .ieatures of the invention are concerned, other apparatus .forpressingtheslide valve 1119 against .theblockJZE might-be used, :forexample one .or

;more;piston \cylin'cler units might be employed.

[515 to exert ia strong rcouple upon the .rod .450 75 s s'troke .and durin these .p QidS .Of iiwell the solenoid I 65 is energized. The pistons 21 are reciprocated during the time that the slidevalve I is stationary, but the amount of reciprocation and the time of reciprocation of the pistons 21 is adjustable. Thus the pistons 21 are moving only when the slide valve I00 is stationary but, in the case of most; adjustments, they are not reciprocating during all of the time that the slide valve is stationary. Furthermore the slide valve IE0 is moving only when the pistons are stationary and preferably the solenoid I65 is deenergized when the slide valve I00 is moving. The important point in this connection, however, is that the solenoid IE or other means for exerting a strong force clamping the slide valve I00. shall be active when the pistons 21 are moving.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinbefore set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodi ments may be made of the above invention and as many changes might be made in the embodiment above set forth, it isto be understood that allmatter hereinbefore setforth or shown the accompanying drawings is to be interpreted as illustrative andnot in a limiting sense.

I claim: r

1. Apparatus of the class described comprising a block having a plurality of pump chambers, a plurality of pistons extending into said chambers, means intermittently reciprocating. said pistons giving said pistons a dwell at the end of each stroke in each direction, discharge passages into which material is pumped, inlet passagesfrom which material is drawn into said chambers, a slide valve having a plurality of each of two sets of ports, one set of ports being shaped to connect the discharge passages to the chambers and the other set being shaped to connect the inlet passages to the chambers, means intermittently reciprocating said slide valve giving ,said valve a dwell at the end of each stroke, an eccentric shaft incontact with said slide valve on the side thereof remote from said block, said eccentric shaft having eccentric cross-section opposite all of said discharge passages and opposite all of said inlet passages whereby when a rotative couple is exerted upon said eccentric shaft tending to turn it the slide valve is strongly urged against the block at all of the discharge and at all of the inlet passages, and means to exert such rotative couple tending to turn said eccentric shaft when the pistons are moving.

2. Apparatus of the class described comprising a block having a plurality of pump chambers, a plurality of pistons extending into said chambers, means intermittently reciprocating said pistons giving said pistons a dwell at the end of each stroke in each direction, discharge passages into which material is pumped, inlet passages from which material is drawn into said chambers, a slide valve having a plurality of each of two sets of ports, one set of ports being shaped to connect the discharge passages to the chambers and the other set being shaped to connect the inlet passages to the chambers, means intermittently reciprocating said slide valve giving said valve a dwell at the end of each stroke, a cam in contact with said slide valve on the side thereof remote from said block whereby when a rotative a piston, a block'having a chamber for the piston and having an inlet passage and having an outlet passage, a. slide valve having a port shaped to connect the chamber with the inlet passage.

andhaving a port shaped to connect the chani. her to the outlet passage, means to reciprocate. the piston intermittently with a dwell at the. end of each stroke, means to reciprocate the slide valve intermittently with a dwell at the end of each stroke, said last two means being. timed to each otherso that the slide valve is, stationary when the piston is moving, means operating when the piston is moving to press said slide valve strongly against said block, said last named means also being associated with. further means-to press said slide valve against said block with a weaker force when said slide valve is moving. I v r I .4. Apparatus of the class described comprising. a plurality of pistons, means for reciprocating the pistons intermittently with a dwell at the end ofeach stroke, a plurality of chambers in which the pistons reciprocate, a slide valve havinga plurality of ports for admitting material to the chambers and a plurality of ports for discharging material from the chambers, a member having a surface against which the slide valve moves, Said: member having passages leading to the chambers, means for reciprocating the slide valve intermittently with a dwell, at the end of each stroke, during one dwell all of the admitting ports beingaligned with the passages and during the other dwell all of the discharging ports beingaligned with. the passagea the means forlreciprocating' the pistons and the means for reciprocatingthe slide valve being connected to a common source of power, and meansfor forcing the slidevalve against the surface with a light force at all times and means forforcing. the slide valve against the surface with a stronger forcewhen the pistons are moving. 1 T I g 5. Apparatus of the. class describedcomprisin'g a plurality of pistons, adjustable means for reciprocating the pistons intermittently with a dwell at the end of each stroke said means being adjustable to vary the length of the strokes, a plurality of chambers in which the pistons reciprocate, a slide valve having a plurality of ports for admitting material to the chambers and a plurality of ports for discharging material from the chambers, a member having a surface against which the slide valve moves, said member having passages leading to the chambers, means for reciprocating the slide valve intermittently with a dwell at the end of each stroke, during one dwell all of the admitting ports being aligned with the passages and during the other dwell all of the discharging ports being aligned with the passages, the means for reciprocating the pistons and the means for reciprocating the slide valve being connected to a common source of power and so timed that when the pistons are moving the slide valve is stationary regardless of the setting of the adjustable means and when the slide valve is moving the pistons are stationary regardless of the setting of the adjustable means, and means for forcing the slide valve against the surface whenever the pistons are moving.

6. Apparatus of the class describedcomprising a plurality of pistons, adjustable means for reciprocating the pistons intermittently with a 11 dwell attire end'of' each stroke said means being adjustable to vary'the' length of the strokes, a plurality of chambers in which the pistons reciprocate, a slide valve having a plurality of ports for admitting material to the chambers and a plurality of ports for discharging material from the chambers, a member having a surface against which the slide valve moves, said member hav-' ing' passages leading to the chambers, means for reciprocating the slide valve intermittently with a dwell at the end of each stroke, during one dwell all of the admitting ports b'eing aligned with the passages and during the other dwell all of the discharging ports being aligned with the passages, the means for reciprocating th pistons and the means for reciprocating the slide valve being connected to a common source of power and so timed that when the pistons are moving the slide valve is stationary regardless of the setting of the adjustable means and when the slide valve is moving the pistons are stationary regardless of the setting of the adjustable means, and means for forcing the-slide valve against the surface with the light force at all times and means for forcing the slide valve against the surface with a stronger force when the pistons are moving.

'7; In apparatus as claimed in claim 4, the combination with the parts and features therein specified, of a device under control of the operator for stopping the slide valve with the ad mitting ports aligned with the passages, whereby continued reciprocation of the pistons agitates material in the chambers and in the passages andin the admitting'ports without pumping it.

8; In apparatus as claimed in claim 5', the combin-ation with the parts and features therein 12 specified; of a device under control of the operator for stopping the slide valve with the'a'dmitting ports aligned with the passages, whereby continued reciprocation of the pistons agitates material in the chambers ancl'in the passages and in the admitting ports without pumping it.

10. Apparatus of the class described comprising a plurality of pistons, means for reciproeating the pistons'intermittently with a dwell at the end" of each stroke, a plurality of chambers in which the pistons reciprocate, a slide valve havinga plurality of ports for admitting material to the chambersand aplurality of ports for discharging material from the chambers, a memher having a surface against which the slide valvemoves, saidmemberhaving passages leading to thechambers, means-vfor reciprocating the slide: valve intermittently with a dwell at the end' of each stroke, during. onedwell all of the admittingports being aligned with thepassa'ges and. during the other: dwell all of? the discharging; port's being aligned with: the passages, the means for reciprocating: the pistons and the means for reciprocating the slide-valve being con-- I nected to acommon sourceof: power, means for REX E MOULE.

References Gited in thefile'of this patent UNITED STATES PATENTS Number Name Date 141,394 Snell July 29, 1873' 1,164,831 McDermott Dec. 21, 1915' 1,327,423 Dryen Jan. 6, 1920 1,343,696 Urie June 15, I920 2,3 i8,958 Celio May 16, 1944 2,356,436 S-cherer Aug. 22, 1944' 

